Method for reading machine-readable marks on racks and receptacles

ABSTRACT

A method of reading machine-readable marks on a movable support and object of a sample instrument. The method includes capturing a first image of the moveable support as the moveable support moves from a first position to a second position using an image capture device; determining whether a first fiducial machine-readable mark on the moveable support is in the first image; determining, when the first fiducial machine-readable mark is in the first image, whether a first machine-readable mark on a first object coupled to the moveable support is in the first image at a predetermined position relative to the first fiducial machine-readable mark; and associating information decoded from the first machine-readable mark on the first object with a first location on the moveable support associated with the first fiducial machine-readable mark.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.17/399,789, filed Aug. 11, 2021, which is a continuation of U.S.application Ser. No. 17/220,954, filed Apr. 2, 2021, now U.S. Pat. No.11,487,959, which is a continuation of U.S. application Ser. No.16/052,448, filed Aug. 1, 2018, now U.S. Pat. No. 10,970,504, which is adivisional of U.S. application Ser. No. 15/332,729, filed Oct. 24, 2016,now U.S. Pat. No. 10,043,047, which claims the benefit of U.S.Provisional Application No. 62/245,930, filed Oct. 23, 2015, thecontents of each of which applications are hereby incorporated byreference in their entirety.

FIELD

Embodiments of this disclosure are directed to systems and methods forreading machine-readable marks on sample racks and receptacles, forexample, racks and receptacles used to perform molecular assays.

BACKGROUND

An assay instrument performs assays on fluid sample material. Forexample, in the clinical laboratory context, the analyzer system can beconfigured to perform multi-step analytical processes (for example, anucleic acid test (NAT) designed to detect microbe, such as a virus or abacterium) that involve adding substances (e.g., fluids), such assamples, solid supports, buffers, oil, primers, polymerases,nucleotides, labels, probes, or other reaction fluids, to and/orremoving substances from receptacles, agitating receptacles to mix thecontents thereof, maintaining and/or altering the temperature of thecontents of the receptacles, heating or chilling the contents of thereceptacles, altering the concentration of one or more contentcomponents of the receptacles, separating or isolating constituentcomponents of the contents of the receptacles, detecting anelectromagnetic signal emission (e.g., light) from the contents of thereceptacles, deactivating or halting an on-going reaction, or anycombination of two or more of such processes.

The assay instrument can be automated to perform the desired analyticalprocess. In such applications, positively matching results of theanalytical process to particular sample is needed. To do this, the assayinstrument needs to know the locations of sample containers placed ontothe instrument. It is also desirable to perform similar tracking ofreagents and consumables used to generate results. This disclosurediscusses a method to track samples, reagents, and consumables using ahand-held or automatic image based barcode reader or similar imagingsystem. In a typical method of sample tracking, sample containers arelabeled with a machine-readable label, e.g., a barcode. The samplecontainer is placed into a holder or rack on an instrument and theinstrument either automatically moves the container or monitors thelocation of a manually moved container. The instrument or operator movesthe samples to a location where a built-in barcode reader reads thelabel on the sample container. The instrument “knows” the location ofthe sample because the instrument actively moved or monitored theposition of a particular sample. The instrument can associate a samplein a particular location or slot in a holder with its barcode and nowall processing of the particular sample can be positively tracked tothat sample's barcode.

Actuators to move samples in front of an on-board barcode reader ormechanisms to allow the operator to move the samples to the reader whilethe instrument monitors position can add cost and size to animplementation of an instrument and can have possible negative effectson the reliability of the instrument. The method discussed in thisdisclosure shows an alternative where a hand-held barcode reader and aspecially labeled rack or labeled positions in the instrument allowpositive association of a sample with a position in a rack or positiveassociation of a reagent or other consumable with a position in aninstrument.

SUMMARY

A method of reading machine-readable marks on a moveable support andobjects of a sample instrument includes capturing a first image of themoveable support as the moveable support moves from a first position toa second position using an image capture device. The method alsoincludes determining whether a first fiducial machine-readable mark onthe moveable support is in the first image. The method also includesdetermining, when the first fiducial machine-readable mark is in thefirst image, whether a first machine-readable mark on an object coupledto the moveable support is in the first image at a predeterminedposition relative to the first fiducial machine-readable mark. Themethod further includes decoding, when the first machine-readable markon the object is in the first image, the first machine-readable mark inthe first image. And the method includes associating information decodedfrom the first machine-readable mark on the object with a first locationon the moveable support associated with the first fiducialmachine-readable mark.

A sample instrument includes a moveable support configured to move froma first position to a second position. The moveable support defines afirst pocket configured to receive a first object having a firstmachine-readable mark. The moveable support also defines a second pocketconfigured to receive a second object having a second machine-readablemark. The moveable support includes a first fiducial machine-readablemark containing information that identifies a location of the firstfiducial machine-readable mark and a second fiducial machine-readablemark containing information that identifies a location of the secondfiducial machine-readable mark. The instrument also includes an imagecapture device having a field of view that captures a first image. Thefirst image includes the first fiducial machine-readable mark and, whenthe first object is received within the first pocket, the firstmachine-readable mark of the first object. The image capture device alsocaptures a second image as the moveable support moves from the firstposition to the second position. The second image includes the secondfiducial machine-readable mark and, when the second object is receivedwithin the second pocket, the second machine-readable mark of the secondobject. The instrument also includes a processor configured to decodethe first machine-readable mark and the first fiducial machine-readablemark in the first image. The processor is configured to associateinformation decoded from the first machine-readable mark with a firstlocation on the moveable support having a predetermined association withthe first fiducial machine-readable mark. The processor can also decodethe second machine-readable mark and the second fiducialmachine-readable mark in the second image. And the processor canassociate information decoded from the second machine-readable mark witha second location on the moveable support having a predeterminedassociation with the second fiducial machine-readable mark.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated herein and form a partof the specification, illustrate the embodiments and, together with thedescription, further serve to explain the principles of the embodimentsand to enable a person skilled in the relevant art(s) to make and usethe embodiments.

FIG. 1 illustrates a partial, perspective view of an analyzer systemthat includes a sample bay according to an embodiment.

FIG. 2 illustrates a cross-sectional plan view of the analyzer system ofFIG. 1 according to an embodiment.

FIG. 3 illustrates a front perspective view of a sample bay according toan embodiment.

FIG. 4 illustrates a partial side view of a sample rack supportingsample receptacles according to an embodiment.

FIG. 5 illustrates a partial side view of a sample rack supportingsample receptacles according to another embodiment.

FIG. 6 illustrates a partial side view of a sample rack supportingsample receptacles according to yet another embodiment.

FIG. 7 illustrates a partial side view of a sample rack supportingsample receptacles according to another embodiment.

FIG. 8 illustrates a partial side view of a sample rack supportingsample receptacles according to yet another embodiment.

FIG. 9 illustrates a front perspective view of a sample bay with a rackpartially inserted into a housing of the sample bay according to anembodiment.

The features and advantages of the embodiments will become more apparentfrom the detailed description set forth below when taken in conjunctionwith the drawings, in which like reference characters identifycorresponding elements throughout. In the drawings, like referencenumbers generally indicate identical, functionally similar, and/orstructurally similar elements.

DETAILED DESCRIPTION

The present invention will now be described in detail with reference toembodiments thereof as illustrated in the accompanying drawings.References to “one embodiment,” “an embodiment,” “some embodiments,”“other embodiments,” “an exemplary embodiment,” “for example,” “anexample,” etc., indicate that the embodiment described may include aparticular feature, structure, or characteristic, but every embodimentmay not necessarily include the particular feature, structure, orcharacteristic. Moreover, such phrases are not necessarily referring tothe same embodiment. Further, when a particular feature, structure, orcharacteristic is described in connection with an embodiment, it issubmitted that it is within the knowledge of one skilled in the art toaffect such feature, structure, or characteristic in connection withother embodiments whether or not explicitly described.

Embodiments described in this application provide systems and methodsfor reading machine-readable marks (for example, one-dimensionalbarcodes, two-dimensional barcodes, alphanumerical characters, symbols,or any other suitable machine-readable mark) on movable supports (forexample, sample racks, reagent drawers, or consumable drawers) andobjects releasably coupled to the moveable supports (for example, samplereceptacles, reagent containers, and consumables) that are used in asample instrument, for example, a sample processing instrument or asample assay instrument. For example, the assay instrument can beconfigured to receive one or more moveable supports that releasably holda plurality of objects each having a machine-readable mark, for example,a one- or two-dimensional barcode. The moveable supports defining aplurality of pockets for receiving the plurality of objects and havingat least one machine-readable fiducial mark that corresponds to eachpocket defined by the moveable support. The location of each of the atleast one machine-readable fiducial mark on the moveable support isknown (i.e., predetermined). The assay instrument can include an imagecapture device, for example, a camera, configured to capture an imagethat includes the machine-readable marks on the sample rack and samplereceptacles. The system also includes a processor that processes thecaptured images to identify and decode machine-readable marks in thecaptured images. The processor can also associate information from theidentified and decoded machine-readable marks on the sample rack withinformation from the corresponding identified and decodedmachine-readable marks on the sample receptacles. Such systems andmethods for reading machine-readable marks on sample racks and samplereceptacles can be used for performing assays on fluid sample materialand for identifying the contents of the sample receptacles, for example,patient information (e.g., patient identification numbers).

In this application, a “sample instrument” is a sample processinginstrument or a sample assay instrument. In this application, a “sampleassay instrument” is any instrument capable of analyzing a sample andrendering a result. For example, any instrument capable of performing ahybridization assay, an amplification assay, a sequencing assay, or animmunoassay on a sample is an assay instrument. Assay instruments canperform an assay directly on a sample without any sample processing, oran assay instrument can further process the sample before performing anassay. Samples that can require some form of sample processing beforesubjecting the samples to the steps of an assay include, in someembodiments, cell samples, tissue samples, stool samples, mucus samples,semen samples, cerebrospinal fluid samples, blood samples, bone marrowsamples, serum samples, urine samples, bile samples, respiratorysamples, sputum samples, and exosome samples, among others. Exemplaryassay instruments include the Tigris® and Panther® systems (Hologic,Inc., San Diego, CA). In this disclosure, a “sample processinginstrument” is any instrument capable of performing a processing step ona sample contained within a receptacle before performing an assay on thesample, but not capable of analyzing a sample and rendering a result.Exemplary sample processing instruments include the Tomcat® instrument(Hologic, Inc., San Diego, CA). In this disclosure, a “sample” is anymaterial to be analyzed, regardless of the source. The material may bein its native form or any stage of processing (e.g., the material may bechemically altered or it may be one or more components of a sample thathave been separated and/or purified from one or more other components ofthe sample). A sample may be obtained from any source, including, butnot limited to, an animal, environmental, food, industrial or watersource. Animal samples include, but are not limited to, peripheralblood, plasma, serum, bone marrow, urine, bile, mucus, phlegm, saliva,cerebrospinal fluid, stool, biopsy tissue including lymph nodes,respiratory tissue or exudates, gastrointestinal tissue, cervical swabsamples, semen or other body or cellular fluids, tissues, or secretions.Samples can be diluted or contained within a receptacle containingdiluents, transport media, preservative solution, or other fluids. Assuch, the term “sample” is intended to encompass samples containedwithin a diluent, transport media, and/or preservative or other fluidintended to hold a sample.

FIGS. 1 and 2 illustrate a perspective view and a plan, cross-sectionalview, respectively, of an exemplary sample instrument 100, namely, asample assay instrument that performs assays on a sample. In someembodiments, sample assay instrument 100 is configured to perform amulti-step analytical process (for example, a nucleic acid test (NAT)designed to detect a microbe, such as a virus or a bacterium) or otherchemical, biochemical or biological processes. Exemplary process stepsinclude, for example, adding substances (e.g., fluids), such as samples,solid supports, buffers, oil, primers, polymerases, nucleotides, labels,probes, or other reaction fluids, to and/or removing substances fromreceptacles, agitating receptacles to mix the contents thereof,maintaining and/or altering the temperature of the contents of thereceptacles (for example, using heated incubators configured to receivea plurality of reaction receptacles and maintain the receptacles in anelevated temperature environment), heating or chilling the contents ofthe receptacles (for example, using temperature ramping stationsconfigured raise the temperature of the contents of reaction receptaclesor chilling modules configured to reduce the temperature of the contentsof the receptacles), altering the concentration of one or more contentcomponents of the receptacles, separating or isolating constituentcomponents of the contents of the receptacles (for example, usingmagnetic separation wash stations configured to isolate a target nucleicacid immobilized on a magnetically-responsive solid support from thecontents of the receptacle), detecting an electromagnetic signalemission (for example, light) from the contents of the receptacles (forexample, using detector configured to detect a signal (e.g., an opticalsignal) emitted by the contents of the reaction receptacle),deactivating or halting an on-going reaction, or any combination of twoor more of such processes. Fluid sample material may include, forexample, urine, blood, plasma, sputum, saliva, mucus, pus, seminalfluid, amniotic fluid, cerebrospinal fluid, synovial fluid, andcultures.

In some embodiments, samples are introduced into sample assay instrument100 via a sample bay 102. FIG. 2 illustrates a cross-sectional, planview of sample assay instrument 100 according to an embodiment. As shownin FIG. 2 , sample assay instrument 100 includes sample bay 102configured to receive a plurality of sample racks, which are describedfurther below. In some embodiments, sample assay instrument 100 alsoincludes a reagent bay 104. Reagent bay 104 is configured to store oneor more containers of reagents used during a multi-step analyticalprocess. In some embodiments, sample assay instrument 100 includes areader 105, for example, an image capture device or a laser barcodereader, configured to read machine-readable marks, for example, one- ortwo-dimensional barcodes, on the reagent containers stored on a moveabledrawer within reagent bay 104. In some embodiments, sample assayinstrument 100 includes one or more moveable tip drawers 106 configuredto store a plurality of tips used by a fluid transfer device (not shownin FIG. 2 ) of sample assay instrument 100. In some embodiments, sampleassay instrument 100 includes a target capture reagent carousel 108configured to support and rotate one or more containers of a targetcapture reagent (TCR). In some embodiments, sample assay instrument 100includes a reader 110, for example, an image capture device or laserbarcode reader, configured to read machine-readable marks, for example,one- or two-dimensional barcodes, on TCR containers on TCR carousel 108.

FIG. 3 illustrates a front perspective view of sample bay 102 accordingto an embodiment. Sample bay 102 is configured to receive a plurality ofsample racks 112 along defined lanes within sample bay 102. Sample racks112 each support a plurality of sample receptacles (not shown in FIG. 3) that each contain a sample. For example, as shown in FIG. 3 , samplebay 102 is configured to receive eight sample racks 112 that move alongdefined lanes within sample bay 102. In other embodiments, sample bay102 is configured to receive less than or more than eight sample racks112.

Sample bay 102 includes a housing 114 that defines an interiorcompartment that receives sample racks 112. Housing 114 can berectangular as shown FIG. 3 or any other suitable shape. In someembodiments, housing 114 includes a base 116 that is, for example,planar and rectangular. Housing 114 also includes a first sidewall 118and a second sidewall 120 extending from opposing sides of base 116, anda back wall (not shown in FIG. 3 ) extending from a back side of base116 between first and second sidewalls 118 and 120. Housing 114 has anopening 122 at its front end to allow sample racks 112 to be insertedinto and removed from the compartment defined by housing 114.

Housing 114 defines a plurality of lanes along which sample racks 112move, for example, eight lanes as shown in FIG. 3 . In some embodiments,base 116 includes a plurality of guides 123 that define the lanes ofhousing 114. Guides 123 can be protrusions that extend from base 116 andare configured to operatively mate with corresponding recesses of sampleracks 112. Guides 123 can help ensure that sample racks 112 areaccurately and repeatedly positioned in the defined lanes of housing 114as sample racks 112 move within the compartment defined by sample bay102. As shown in FIG. 3 , the lanes are straight and extend from thefront end of housing 114 to the back end of housing 114.

In some embodiments, housing 114 also includes a top panel 124. In someembodiments, top panel 124 includes a plurality of guides 126 thatdefine, along with guides 123, the lanes in which sample racks 112 move.Guides 126 can be protrusions that extend from top panel 124 toward base116 and that are configured to operatively mate with correspondingrecesses on sample racks 112. In some embodiments, top panel 124 definesa plurality of sample receptacle access openings 127, which in someembodiments as shown in FIG. 3 , are arranged in a rectangular array ofrows and columns. Each column of openings 126 is aligned with arespective sample rack 112, providing assay instrument 101, for example,easy access to receptacles held by sample racks 112.

Sample bay 102 also includes an image capture device 128 configured tocapture images of machine-readable marks (for example, one-dimensionalbarcodes, two-dimensional barcodes, alphanumerical characters, symbols,and any other suitable machine-readable mark) on sample racks 112, andto capture images of machine-readable marks (for example,one-dimensional barcodes, two-dimensional barcodes, alphanumericalcharacters, symbols, and any other suitable machine-readable mark) onsample receptacles supported by sample racks 112. In some embodiments,as shown in FIG. 3 , sample bay 102 includes an image capture devicesupport 130 configured to support image capture device 128 and fixedlycoupled to housing 114. Image capture device 128 is coupled to imagecapture device support 130 and, thus, fixedly coupled to housing 114. Asshown in FIG. 3 , image capture device support 130 is coupled to housing114, for example, fixedly coupled to side wall 120. In some embodiments,when viewed from above, image capture device support 130 issubstantially U-shaped and forms a compartment sized to receive andsupport image capture device 128. And image capture device 128 iscoupled to image capture device support 130, fixing the position ofimage capture device 128 relative to housing 114 in some embodiments.

Side wall 120 can define an opening 132 extending into the interiorcompartment defined by housing 114 such that image capture device 128can read labels on sample racks 112 within housing 114 through opening132. In some embodiments, image capture device 128 is configured to readmachine-readable marks as sample racks 112 are inserted into or removedfrom housing 114. In other embodiments, image capture device 128 isconfigured to read machine-readable marks after sample racks 112 arefully inserted into housing 114.

In some embodiments, image capture device 128 is disposed outside ofhousing 114 and spaced from opening 132 as shown in FIG. 3 . In otherembodiments (not shown), image capture device 128 is disposed outside ofhousing 114 and directly adjacent opening 132, or image capture device128 is disposed within housing 114. In yet other embodiments, imagecapture device 128 is a hand-held device separate from housing 114 thata user manually operates to read machine-readable marks on sample racks112 and receptacles held by racks 112 before being inserted withinsample bay 102.

In some embodiments, as shown in FIG. 3 , sample bay 102 includes alight source, for example, a strobe light, configured to illuminate theinterior of housing 114. For example, light source can illuminatemachine-readable marks on sample racks 112 and sample receptacles heldby sample racks 112 within housing 114. As shown in FIG. 3 , forexample, light source is near image capture device 128 and coupled toimage capture device support 130. In some embodiments, light sourceincludes an array of LEDs. In some embodiments (not shown), light sourceis disposed inside housing 114 or at any other suitable location. Insome embodiments, light source is embodied within image capture device128.

As best seen in FIGS. 3 and 9 , each sample rack 112 can include ahandle 144 configured to allow a user to grasp and manually move samplerack 112 in some embodiments. For example, a user can grasp handle 144to insert or remove sample rack 112 from housing 114 of sample bay 102.In some embodiments, as best seen in FIG. 9 , handle 144 defines anopening 146 that is configured to allow a user's fingers to passthrough. And in some embodiments, opening 146 allows the optical pathalong which image capture device 128 captures an image to pass throughone sample rack 112 to read a machine-readable mark on another samplerack 112 positioned on the other side of opening 146 from image capturedevice 128.

In some embodiments, as shown in FIG. 9 , sample rack 112 includes arack identifier that provides unique rack-identifying information, forexample, a rack identification number. In some embodiments (not shown),the rack identifier is an RFID tag. In such RFID embodiments, sample bay102 includes an RFID reader configured to interrogate the RFID tag whensample rack 112 is within sample bay 102. In other embodiments (as shownin FIG. 9 ), the rack identifier is a machine-readable mark 148, forexample, a one- (as shown in FIG. 9 ) or two-dimensional barcode. Imagecapture device 128 can be configured to capture an image that includesrack-identifying machine-readable mark 148. Rack-identifying,machine-readable mark 148 can be positioned near handle 144 of samplerack 112, as shown in FIG. 9 , in some embodiments.

FIGS. 4-8 illustrate various embodiments of sample rack 112, samplereceptacles 136, and the field of view of image capture device 128.

Referring to FIG. 4 , sample rack 112 is configured to hold a pluralityof sample receptacles 136. For example, sample rack 112 can beconfigured to hold fifteen sample receptacles 136. Sample receptacles136 can be any type of fluid container, including, for example, a tube,vial, cuvette, cartridge, microtiter plate, etc. that is configured tocontain a sample at any point during processing of the sample. In someembodiments, each sample receptacle 136 supported by sample rack 112includes at least one machine-readable mark 147. Machine-readable mark147 can be, (for example, one-dimensional barcodes (as shown in FIGS. 4,5, and 6 ), two-dimensional barcodes (as shown in FIGS. 7 and 8 ),alphanumerical characters, symbols, and any other suitablemachine-readable mark. One-dimensional barcodes express information inone direction, for example, either the horizontal direction or thevertical direction. Examples of one-dimensional barcodes include Code 39codes, Code 128 codes, Interleaved 2 of 5 codes, and Codabar codes.Two-dimensional barcodes express information in two directions, forexample, in the horizontal and vertical directions, and include stackedbarcodes and matrix barcodes. Examples of two-dimensional barcodesinclude Aztec codes, PDF417 codes, MaxiCodes, Codablock codes, DataMatrix codes, and QR codes. Two-dimensional barcodes can improvedecoding accuracy and increase the amount of information containedwithin the barcode relative to a one-dimensional barcode. In someembodiments, machine-readable mark 147 for each receptacle 136 containsone or more of the following items of information: patient informationsuch as a unique patient identifier (for example, patient name orpatient identification number), patient metadata (for example, date ofbirth, age, sex, height, or weight), medical history, or any otherdesired patient information; and sample information such as thehealthcare provider requesting the assay, the sample type, the date thesample was collected, the collection site, the type of assays to beperformed, assay test results, and other suitable information.

As shown in FIG. 4 , sample rack 112 includes a base 138 that defines aplurality of pockets 140 for closely receiving sample receptacles 136.Pockets 140 can be separated from each other by a vertical dividing wall142 in some embodiments. As shown in FIG. 4 , vertical dividing walls142 are configured to form gaps there between such that, when areceptacle 136 is placed within a pocket 140, machine-readable mark 147on sample receptacle 136 is visible to image capture device 128.

Sample rack 112 includes at least one fiducial machine-readable mark 150and, in some embodiments, at least one fiducial machine-readable markfor each pocket 140 of sample rack 112. Fiducial machine-readable marks150 can be, for example, one-dimensional barcodes, two-dimensionalbarcodes (as shown in FIGS. 4-8 ), alphanumerical characters, symbols,and any other suitable machine-readable mark. Two-dimensional barcodescan improve decoding accuracy and increase the amount of informationcontained within fiducial machine-readable mark 150. In someembodiments, each fiducial machine-readable mark 150 containsinformation that can be used to identify the location of the fiducialmachine-readable mark 150 on sample rack 112. For example, each fiducialmachine-readable mark 150 can contain unique information, for example, aunique identification number, value, or letter, that has a knownassociation with a specific location on sample rack 112. Theseassociations between the fiducial machine-readable marks 150, including,for example, unique information contained in the fiducialmachine-readable marks 150, and the specific locations on sample rack112 can be stored in a memory of sample assay instrument 100 in someembodiments.

In some embodiments, fiducial machine-readable marks 150 are located onthe outer surface of dividing walls 142 that separate adjacent pockets140 from each other. In other embodiments (described further below),fiducial machine-readable marks 150 are located on a cover configured tofit over the top of sample receptacles 136 held within pockets 140 ofsample rack 112. In other embodiments (described further below),fiducial machine-readable marks 150 are located on a portion of base 138of sample rack 112 that is below pockets 140 of sample rack 112.

In some embodiments, as shown in FIGS. 4 and 5 , sample rack 112 caninclude one fiducial machine-readable mark 150 on a left and right sideof each pocket 140. And in some embodiments, as shown in FIGS. 4 and 5 ,fiducial machine-readable marks 150 are linearly (e.g., horizontally)aligned. In some embodiments, as shown in FIG. 6 , sample rack 112 caninclude two vertically aligned fiducial machine-readable marks 150 on aleft and right side of each pocket 140. In some embodiments, as shown inFIG. 7 , sample rack 112 can include one fiducial machine-readable mark150 on a top and bottom side of each pocket 140. And in someembodiments, as shown in FIG. 8 , sample rack 112 can include onefiducial machine-readable mark 150 below and vertically aligned witheach pocket 140.

Sample rack 112 can also include a machine-readable mark 158 within eachpocket 140 of sample rack 112 in some embodiments. Machine-readablemarks 158 can be, for example, one-dimensional barcodes (as shown inFIGS. 4-8 ), two-dimensional barcodes, alphanumerical characters,symbols, and any other suitable machine-readable mark. Machine-readablemarks 158 are positioned within each pocket 140 such that they arevisible to image capture device 128 when a sample receptacle 136 is notreceived within the corresponding pocket 140. For example, as shown inFIG. 4 , empty pocket identifying machine-readable marks 158 are shownin pockets 140D and 140E of sample rack 112 because these two pockets140D and 140E are not holding a sample receptacle 136.

The positions of machine-readable marks 147 on sample receptacles 136relative to respective fiducial machine-readable mark(s) 150 when samplereceptacles 136 are placed in pockets 140 are known, and the positionsof empty pocket identifying machine-readable marks 158 on sample rack112 relative to respective fiducial machine-readable mark(s) 150 areknown. These known relative positions can be saved in a memory of sampleassay instrument 100.

In some embodiments, as shown in FIG. 4 , image capture device 128 has afield of view sufficient to capture images that include (1) at least onefiducial machine-readable mark 150 and (2) at least one of (a) at leastone machine-readable mark 147 on at least one sample receptacle 136received in respective pockets 140 and (b) at least one empty pocketidentifying machine-readable mark 158 in respective pockets 140. Forexample, as shown in FIG. 4 , image capture device 128 has a field ofview that captures an image that includes (1) a pair of fiducialmachine-readable marks 150 (one mark 150 on a left side of a respectivepocket 140 and one mark 150 on a right side of a respective pocket 140)and (2) either a machine-readable mark 147 on the sample receptacle 136received in the respective pocket or an empty-pocket identifyingmachine-readable mark 158 in the respective pocket 140 if the respectivepocket 140 is empty. As shown in FIG. 4 , image capture device 128 has afield of view sufficient to capture image 152A that includes (1)fiducial machine-readable mark 150A on a left side of pocket 140A, (2)fiducial machine-readable mark 150B on a right side of pocket 140A, and(3) machine-readable mark 147 on sample receptacle 136 in pocket 140A.Image capture device 128 has a field of view sufficient to subsequentlycapture image 152B (as sample rack 112 is inserted within sample bay102) that includes (1) fiducial machine-readable mark 150B on a leftside of pocket 140B, (2) fiducial machine-readable mark 150C on a rightside of pocket 140B, and (3) machine-readable mark 147 on samplereceptacle 136 in pocket 140B. Image capture device 128 can subsequentlycapture similar images of fiducial machine-readable marks 150C, 150D,150E, etc. and machine-readable marks 147 on sample receptacles 136 inpockets 140C, 140D, 140E, etc.

In some embodiments, as shown in FIG. 5 , image capture device 128 has afield of view that captures an image that includes (1) only one fiducialmachine-readable mark 150 (e.g., mark 150 on a left side of a respectivepocket 140) and (2) either a machine-readable mark 147 on the samplereceptacle 136 received in the respective pocket 140 or an empty-pocketidentifying machine-readable mark 158 in the respective pocket 140 ifthe respective pocket 140 is empty. As shown in FIG. 5 , image capturedevice 128 has a field of view sufficient to capture image 152A thatincludes (1) fiducial machine-readable mark 150A on a left side ofpocket 140A, and (2) machine-readable mark 147 on sample receptacle 136in pocket 140A (or machine-readable mark 158 if no sample receptacle 136is in pocket 140A). Image capture device 128 has a field of viewsufficient to subsequently capture image 152B (as sample rack 112 isinserted within sample bay 102) that includes (1) fiducialmachine-readable mark 150B on a left side of pocket 140B, and (2)machine-readable mark 147 on sample receptacle 136 in pocket 140B (ormachine-readable mark 158 if no sample receptacle 136 is in pocket140B). Image capture device 128 has a field of view sufficient tosubsequently capture image 152C (as sample rack 112 is further insertedwithin sample bay 102) that includes (1) fiducial machine-readable mark150C on a left side of pocket 140C, and (2) machine-readable mark 147 onsample receptacle 136 in pocket 140C (or machine-readable mark 158 if nosample receptacle 136 is in pocket 140C). Image capture device 128 cansubsequently capture similar images of fiducial machine-readable marks150D, 150E, etc. and machine-readable marks 147 on sample receptacles136 in pockets 140D, 140E, etc. (or machine-readable marks 158 if nosample receptacles 136 are in pocket 140D, 140E, etc.).

As shown in FIG. 6 , image capture device 128 has a field of viewsufficient to capture an image that includes (1) a pair of fiducialmachine-readable marks 150 on a left side of a respective pocket 140 anda pair of fiducial machine-readable marks 150 on a right side of therespective pocket 140) and (2) either a machine-readable mark 147 on thesample receptacle 136 received in the respective pocket or anempty-pocket identifying machine-readable mark 158 in the respectivepocket 140 if the respective pocket 140 is empty. As shown in FIG. 6 ,image capture device 128 has a field of view sufficient to capture image152A that includes (1) fiducial machine-readable marks 150A and 150A′ ona left side of pocket 140A, (2) fiducial machine-readable marks 150B and150B′ on a right side of pocket 140A, and (3) machine-readable mark 147on sample receptacle 136 in pocket 140A. Image capture device 128 has afield of view sufficient to subsequently capture image 152B (as samplerack 112 is inserted within sample bay 102) that includes (1) fiducialmachine-readable marks 150B and 150B′ on a left side of pocket 140B, (2)fiducial machine-readable marks 150C and 150C′ on a right side of pocket140B, and (3) machine-readable mark 147 on sample receptacle 136 inpocket 140B. Image capture device 128 can subsequently capture similarimages of fiducial machine-readable marks 150C, 150C′, 150D, 150D′,150E, 150E′, etc. and machine-readable marks 147 on sample receptacles136 in pockets 140C, 140D, 140E, etc. (or machine-readable marks 158 ifno sample receptacles 136 are in pocket 140C, 140D, 140E, etc.).

As shown in FIG. 7 , image capture device 128 has a field of viewsufficient to capture images that each include (1) a pair of fiducialmachine-readable marks 150 (one mark 150 on a top side of a respectivepocket 140 and one mark 150 on a bottom side of a respective pocket 140)and (2) either a machine-readable mark 147 on the sample receptacle 136received in the respective pocket or an empty-pocket identifyingmachine-readable mark 158 in the respective pocket 140 if the respectivepocket 140 is empty. As shown in FIG. 7 , image capture device 128 has afield of view sufficient to capture image 152A that includes (1)fiducial machine-readable mark 150A on a top side of pocket 140A, (2)fiducial machine-readable mark 150A′ on a bottom side of pocket 140A,and (3) machine-readable mark 147 on sample receptacle 136 in pocket140A. Image capture device 128 has a field of view sufficient tosubsequently capture image 152B (as sample rack 112 is inserted withinsample bay 102) that includes (1) fiducial machine-readable mark 150B ona top side of pocket 140B, (2) fiducial machine-readable mark 150B′ on abottom side of pocket 140B, and (3) machine-readable mark 147 on samplereceptacle 136 in pocket 140B. Image capture device 128 has a field ofview sufficient to subsequently capture image 152C (as sample rack 112is further inserted within sample bay 102) that includes (1) fiducialmachine-readable mark 150C on a top side of pocket 140C, (2) fiducialmachine-readable mark 150C′ on a bottom side of pocket 140C, and (3)machine-readable mark 147 on sample receptacle 136 in pocket 140C (ormachine-readable mark 158 if no sample receptacle 136 is in pocket140C). Image capture device 128 can subsequently capture similar imagesof fiducial machine-readable marks 150D, 150D′, 150E, 150E′, etc. andmachine-readable marks 147 on sample receptacles 136 in pockets 140D,140E, etc. (or machine-readable marks 158 if no sample receptacles 136are in pocket 140D, 140E, etc.).

As shown in FIG. 7 , sample rack 112 includes a cover 151 configured tobe releasably secured to base 138 of sample rack 112 in someembodiments. In some embodiments, fiducial machine-readable marks150A-150E are disposed on cover 151, and fiducial machine-readable marks150A′-150E′ are disposed on a portion 154 of base 138 of sample rack 112that is below pockets 140. In some embodiments, cover 151 also includesa machine-readable mark 156, for example, a one- (as shown in FIG. 9 )or two-dimensional barcode. Label 156 is configured to be used todetermine whether cover 151 is coupled to base 138 and/or positionedproperly relative to base 138.

As shown in FIG. 8 , image capture device 128 has a field of viewsufficient to capture image 152A that includes (1) fiducialmachine-readable mark 150A on a bottom side of pocket 140A, and (2)machine-readable mark 147 on sample receptacle 136 in pocket 140A (ormachine-readable mark 158 if no sample receptacle 136 is in pocket140A). Image capture device 128 has a field of view sufficient tosubsequently capture image 152B (as sample rack 112 is inserted withinsample bay 102) that includes (1) fiducial machine-readable mark 150B ona bottom side of pocket 140B, and (2) machine-readable mark 147 onsample receptacle 136 in pocket 140B (or machine-readable mark 158 if nosample receptacle 136 is in pocket 140B). Image capture device 128 has afield of view sufficient to subsequently capture image 152C (as samplerack 112 is further inserted within sample bay 102) that includes (1)fiducial machine-readable mark 150C on a bottom side of pocket 140C, and(2) machine-readable mark 147 on sample receptacle 136 in pocket 140C(or machine-readable mark 158 if no sample receptacle 136 is in pocket140C). Image capture device 128 can subsequently capture similar imagesof fiducial machine-readable marks 150D, 150E, etc. and machine-readablemarks 147 on sample receptacles 136 in pockets 140D, 140E, etc. (ormachine-readable marks 158 if no sample receptacles 136 are in pocket140D, 140E, etc.).

Image capture device 128 can be configured to have a working distancerange that includes each lane defined by sample bay 102 within housing114 along which sample racks 112 move.

Sample assay instrument 100 can include a processor configured toprocess images captured by image capture device 128 to associateinformation contained in machine-readable marks 147 on each samplereceptacle 136 on sample rack 112 with a specific location, for example,with a specific pocket 140, on sample rack 112. For example, theprocessor can process a captured image to identify at least one fiducialmachine-readable mark 150 in the image. And then based on the known,predetermined position of a respective machine-readable mark 147 on asample receptacle 136 relative to the identified fiducialmachine-readable mark 150, the processor can identify and decode therespective machine-readable mark 147 on a respective sample receptacle136. The processor can then associate information decoded from therespective machine-readable mark 147 with a specific location or pocketon sample rack 112 that is known to be associated with the identifiedfiducial machine-readable mark 150 in the image.

The processor can also save, into a memory of sample assay instrument100, this association of information decoded from the respectivemachine-readable mark 147 with a specific location or pocket on samplerack 112 in some embodiments.

In some embodiments, for example, the processor determines if an imagecaptured by image capture device 128 includes a fiducialmachine-readable mark 150. In some embodiments, the processor processesthe entire captured image to determine the presence of a fiducialmachine-readable mark 150. In other embodiments, the processor processesonly a portion of the captured image known to include fiducialmachine-readable marks 150 to determine the presence of a fiducialmachine-readable mark 150 in the captured image.

If the captured image does not include a fiducial machine-readable mark150, the processor starts processing the next captured image.

If the captured image does include a fiducial machine-readable mark 150,the processor determines if the captured image includes amachine-readable mark at a known position relative to the identifiedfiducial machine-readable mark 150 in the captured image thatcorresponds to a position at which a machine-readable mark 147 on samplereceptacle 136 would be if a sample receptacle 136 is in the pocket 140associated with the identified fiducial machine-readable mark 150. Insome embodiments, the processor processes the entire captured image todetermine whether a machine-readable mark is at the known relativeposition. In other embodiments, the processor processes only a portionof the captured image that includes the known relative position todetermine whether a machine-readable mark is at the known relativeposition. If the captured image does include a machine-readable mark 147at the known relative position, the processor decodes themachine-readable mark 147 and associates the decoded information with aspecific location or pocket on sample rack 112 that is known to beassociated with the identified fiducial machine-readable mark 150 in thecaptured image. The processor can then store this association in amemory of sample assay instrument 100. Then the processor can startprocessing the next captured image, repeating the above steps.

If the captured image does not include a machine-readable mark 147 atthe known position, the processor determines if the captured imageincludes a machine-readable mark at a known position relative to theidentified fiducial machine-readable mark 150 in the captured image thatcorresponds to a position at which a machine-readable mark 158 would beif a receptacle 136 was not in the pocket 140 associated with theidentified fiducial machine-readable mark 150. If the captured imagedoes include a machine-readable mark 158, the processor startsprocessing the next captured image, repeating the above steps. In someembodiments, the processor processes the entire captured image todetermine whether a machine-readable mark 158 is at the known relativeposition. In other embodiments, the processor processes only a portionof the captured image that includes the known relative position todetermine whether a machine-readable mark 158 is at the known relativeposition.

For example, referencing either FIG. 5 or FIG. 8 , the processorprocesses captured image 152A and determines, for example, by processinga portion of image 152A or the entire image 152A, that image 152Aincludes a fiducial machine-readable mark 150A. The processor thendetermines, for example, by processing the entire image 152A or aportion of image 152A, that the captured image 152A includes amachine-readable mark 147 at a known position relative to the identifiedfiducial machine-readable mark 150A in the captured image 152A thatcorresponds to a position at which a machine-readable mark 147 on samplereceptacle 136 would be if a receptacle 136 is in pocket 140A associatedwith the identified fiducial machine-readable mark 150A. Next theprocessor decodes the machine-readable mark 147 in image 152A andassociates the decoded information with a specific location or pocket onsample rack 112 that is known to be associated with the identifiedfiducial machine-readable mark 150 in captured image 152A. The processorcan then store this association in a memory of sample assay instrument100. Then the processor can start processing the next captured image152B repeating the above steps.

In another processing embodiment, the processor processes each imagecaptured by image capture device 128 to identify each machine-readablemark within the captured image 152. Next, the processor determines ifany one of the identified machine-readable marks in the captured imageis a fiducial machine-readable mark 150 on sample rack 112. If theidentified machine-readable marks in the captured image includes afiducial machine-readable mark 150, the processor then determines if anyof the identified machine-readable marks in the captured image islocated at a known position relative to the identified machine-readablemark(s) 150 in the captured image that corresponds to a position atwhich a machine-readable mark 147 on receptacle 136 would be if areceptacle 136 is in the corresponding pocket 140 associated with theidentified fiducial machine-readable mark(s) 150. If the identifiedmachine-readable marks in captured image 152 includes a machine-readablemark 147 at the know position relative to the identifiedmachine-readable mark(s) 150 in the captured image, the processordecodes the machine-readable mark 147 and associates the decodedinformation within the machine-readable mark 147 with a specificlocation or pocket 140 that corresponds to the identifiedmachine-readable mark(s) 150. The processor can then store thisassociation in a memory of sample assay instrument 100. If theidentified machine-readable marks in the captured image does not includea machine-readable mark 158 at the known position relative to theidentified machine-readable mark(s) 150 in the captured image 152 thatcorresponds to a position at which either a machine-readable mark 147 onreceptacle 136 would be if a receptacle 136 is in the correspondingpocket 140, the processor then determines if any of the identifiedmachine-readable marks in the captured image is located at a knownposition relative to the identified machine-readable mark(s) 150 in thecaptured image that corresponds to a position at which amachine-readable mark 158 in corresponding empty pocket 140 associatedwith the identified fiducial machine-readable mark(s) 150. If theidentified machine-readable marks in captured image 152 includes amachine-readable mark 158 at the known position relative to theidentified machine-readable mark(s) 150 in the captured image, theprocessor decodes the machine-readable mark 158 and associates an emptystatus with the specific location or pocket 140 that corresponds to theidentified machine-readable mark(s) 150. The processor can then storethis association in a memory of sample assay instrument 100. Theprocessor can repeat these steps for each captured image 152.

In some embodiments, sample bay 102 is configured such that sample racks112 are manually inserted within housing 114 of sample bay 102. In thisdisclosure, “manually inserted,” “manually moved,” or similar phrasesmean that sample racks 112 are inserted or moved without using automatedor electrical device components. That is, sample racks 112 are insertedor moved within housing 114 along the defined lanes using only theuser's hands. When sample racks 112 are manually moved, sample racks 112can move at a high speed that exceeds 100 mm/sec, for example, speedsgreater than 300 mm/sec, 500 mm/sec, 600 mm/sec, or 1000 mm/sec, in someembodiments.

In other embodiments, sample bay 102 is configured to automatically movesample rack 112 within housing 114 of sample bay 102. For example,sample bay 102 can include an automated actuator that moves sample racks112 within housing 114 of sample bay 102 to a fully inserted position.In some embodiments, sample rack 112 is automatically moved withinhousing 114 at a known, constant speed.

Referencing FIG. 9 , to insert a sample rack 112 within housing 114 ofsample bay 102, a user aligns sample rack 112 with guides 123 on base116. The user then moves sample rack 112 in a direction 158 (as shown inFIG. 9 ) along a lane defined by guides 123 from a first, initialposition to a second, fully inserted position within housing 114 ofsample bay 102. As shown FIG. 9 , sample receptacles 136 are placed insample rack 112 such that machine-readable marks 147 are aligned withthe openings defined by the dividing walls 142 that separate adjacentpockets 140 from each other. Accordingly, machine-readable marks 147 arevisible to image capture device 128 through opening 132 defined in sidewall 120 of housing 114. Thus, as sample rack 112 moves from the initialposition to the fully inserted position, image capture device 128 canread machine-readable marks 147 on each sample receptacle 136 on samplerack 112, as well as pocket identifying fiducial machine-readable marks150, rack identifying machine-readable mark 148, cover identifyingmachine-readable mark 156, and empty pocket identifying machine-readablemark 158.

In some embodiments, image capture device 128 has a field of viewconfigured to capture image 152. Image capture device 128 can have aworking distance range large enough to include each lane defined inhousing 114, along which sample racks 112 move in some embodiments.

In some embodiments, the image capture device 128 has a sufficient depthof field such that each of fiducial machine-readable marks 150,machine-readable marks 147 on each sample receptacle 136, rackidentifying machine-readable mark 148, cover identifyingmachine-readable mark 156, and empty pocket identifying machine-readablemark 158 are sufficiently in focus in the captured images to allow theprocessor to process the captured images as described above. Forexample, fiducial machine-readable marks 150, rack identifyingmachine-readable mark 148, and cover identifying machine-readable mark156 are substantially located in the same plane as shown in FIG. 9 , butmachine-readable marks 147 on each sample receptacle 136 andempty-pocket identifying machine-readable mark 158 can be offset fromthat plane in a direction away from image capture device 128 due to thelocation on receptacle 136 and the wall of pocket 140 on whichmachine-readable marks 147 and empty-pocket identifying machine-readablemark 158, respectively, are located in some embodiments. In someembodiments, image capture device 128 can have a sufficient depth offield, for example, such that each of these machine-readable marks arein sufficient focus in the captured image to allow for theabove-described processing. In some embodiments, the depth of focus canbe about 1 inch, which can be about the diameter of pocket 140 in someembodiments.

In some embodiments, image capture device 128 is a camera. Exemplarycameras include a charge-coupled device (CCD) camera or complementarymetal-oxide-semiconductor (CMOS) camera. In some embodiments, imagecapture device 128 captures a plurality of images 152 at a ratesufficient to acquire an image of machine-readable marks 147 on eachsample receptacle 136, fiducial machine-readable marks 150, rackidentifying machine-readable mark 148, cover identifyingmachine-readable mark 156, and empty-pocket identifying machine-readablemark 158 when on sample rack 112 is moving at a rate up to at least 1000mm/sec, including for example 100 mm/sec, 300 mm/sec, 500 mm/sec, and600 mm/sec. For example, in some embodiments, image capture device 128captures an image 152 at a rate of at least 20 Hz, such as 25 Hz, 35 Hz,50 Hz or 60 Hz.

Referencing FIG. 9 , as sample rack 112 is inserted into sample bay 102along a lane defined by guides 123 (and in direction 158), image capturedevice 128 acquires a plurality of images of sample rack 112 andreceptacles 136 contained therein as it passes through the field of viewof image capture device 128. For example, the acquired images 152 caninclude machine-readable marks 147 on each sample receptacle 136,fiducial machine-readable marks 150, rack identifying machine-readablemark 148, cover identifying machine-readable mark 156, and empty pocketidentifying machine-readable mark 158. In some embodiments, the acquiredimages 152 are transmitted to the processor that is configured toprocess the acquired images as described above. In some embodiments, theprocessor is coupled to or disposed in housing 114. In some embodiments,this image processing by the processor occurs while the sample rack isbeing inserted within housing 114. In other embodiments, this imageprocessing by the processor occurs after sample rack 112 is fullyinserted into housing 114 of sample bay 102.

In some embodiments, the processor is also configured to activate thelight source when sample rack 112 each time an image 152 is captured.Using the light source when acquiring image 152 can further reduce thenecessary performance requirement(s) of image capture device 128.

Although the above-described embodiments include a sample rack 112 andsample receptacles 136, the embodiments are not limited to sample racks112 and sample receptacles 136. For example, these embodiments can beapplied to other racks and fixtures of sample assay instrument 100 thathold reagent containers or other processing consumables. Accordingly,the above-described embodiments can be used to determine the position ofthe reagent containers or other processing consumables relative to therack or fixture on which the respective reagent containers or otherprocessing consumables are placed.

Although the above-described embodiments include an image capture device128 that is fixedly coupled to sample bay 102, the disclosed embodimentsare not limited to fixed readers 128. For example, these embodiments canbe applied using a handheld reader that the user manually operates. Suchhand-held embodiments can help address user variability that may resultin receptacles 136 being scanned non-sequential order.

Some embodiments are implemented via control and computing hardwarecomponents, user-created software, data input components, and dataoutput components. Hardware components include, for example, theprocessor, such as a microprocessor or computer, configured to effectcomputational and/or control steps by receiving one or more inputvalues, executing one or more algorithms stored on non-transitorymachine-readable media (e.g., software) that provide instruction formanipulating or otherwise acting on the input values, and output one ormore output values. Such outputs may be displayed or otherwise indicatedto an operator for providing information to the operator, for exampleinformation as to the status of the instrument or a process beingperformed thereby, or such outputs may comprise inputs to otherprocesses and/or control algorithms. Data input components compriseelements by which data is input for use by the control and computinghardware components. Such data inputs may comprise image capturedevices, positions sensors, motor encoders, as well as manual inputelements, such as graphic user interfaces, keyboards, touch screens,microphones, switches, manually operated scanners, voice-activatedinput, etc. Data output components may comprise hard drives or otherstorage media, graphic user interfaces, monitors, printers, indicatorlights, or audible signal elements (e.g., buzzer, horn, bell, etc.). Insome embodiments, the processor can comprise a single module thatperforms image processing and system control. In other embodiments, theprocessor comprises a plurality of modules that perform discreteprocessing and control steps. In some embodiments, the processor can bea component of image capture device 128 that processes (for example,post-processing) images stored in a buffer of image capture device 128.

Software comprises instructions stored on non-transitorycomputer-readable media which, when executed by the control andcomputing hardware, cause the control and computing hardware to performone or more automated or semi-automated processes. In some embodiments,the software for image processing is stored in memory on image capturedevice 128, for example. In some embodiments, the software for imageprocessing is stored in external memory in communication with theprocessor.

It is to be appreciated that the Detailed Description section, and notthe Summary and Abstract sections, is intended to be used to interpretthe claims. The Summary and Abstract sections may set forth one or morebut not all exemplary embodiments of the present invention ascontemplated by the inventor(s), and thus, are not intended to limit thepresent invention and the appended claims in any way.

The present invention has been described above with the aid offunctional building blocks illustrating the implementation of specifiedfunctions and relationships thereof. The boundaries of these functionalbuilding blocks have been arbitrarily defined herein for the convenienceof the description. Alternate boundaries can be defined so long as thespecified functions and relationships thereof are appropriatelyperformed.

The foregoing description of the specific embodiments will so fullyreveal the general nature of the invention that others can, by applyingknowledge within the skill of the art, readily modify and/or adapt forvarious applications such specific embodiments, without undueexperimentation, without departing from the general concept of thepresent invention. Therefore, such adaptations and modifications areintended to be within the meaning and range of equivalents of thedisclosed embodiments, based on the teaching and guidance presentedherein. It is to be understood that the phraseology or terminologyherein is for the purpose of description and not of limitation, suchthat the terminology or phraseology of the present specification is tobe interpreted by the skilled artisan in light of the teachings andguidance.

The breadth and scope of the present invention should not be limited byany of the above-described exemplary embodiments, but should be definedonly in accordance with the following claims and their equivalents.

What is claimed is:
 1. A method of reading machine-readable marks on amoveable support and objects of a sample instrument, comprising:capturing a first image of the moveable support as the moveable supportmoves from a first position to a second position using an image capturedevice; determining whether a first fiducial machine-readable mark onthe moveable support is in the first image; determining, when the firstfiducial machine-readable mark is in the first image, whether a firstmachine-readable mark on an object coupled to the moveable support is inthe first image at a predetermined position relative to the firstfiducial machine-readable mark; and associating information decoded fromthe first machine-readable mark on the object with a first location onthe moveable support associated with the first fiducial machine-readablemark.